Transcript Early Growth of Ramon (Brosimum alicastrum Sw.) and

Early Growth of Ramon
(Brosimum alicastrum Sw.)
and Relationships Between
Seed Weight and
Seedling Size
Anibal Niembro
Instituto de Ecologia, A.C. Xalapa, Veracruz, Mexico.
C.P. 91070f
Brosimum alicastrum Sw.
Heavier Seed = Larger Seedling?
Faster germination
Greater vigor
Greater growth
potential
Morphological
uniformity
Materials and Methods
Collection of bulk
sample
200 randomly
chosen seeds
Seeds were
weighed and
planted
Materials and Methods
Growth was measured by monitoring:
Emergence rate
Seedling height
Main root length
Stem diameter
Number of leaves
Stem and leaf fresh and dry weight
Root fresh and dry weight
Sturdiness quotient
Shoot/root ratio
Materials and Methods
Descriptive statistics:
Mean, standard deviation, standard error,
90% CI, minimum and maximum
values, and the range of coefficient of
variability.
Correlation analysis
Relationship between seed weight and
other variables.
Results & Discussion – Seed
Weight and Emergence
184 seeds germinated
Seed weight ranged from 0.65 – 6.02 g
Emergence began 12 days after sowing
and continued for 27 days; average time
to germination: 17.8 days
Results & Discussion: Seedling
Growth and Development
Morphological Trait
Minimum Maximum Mean
Value
Value
Height
Main root length
Stem diameter
Number of leaves
8.60
3.00
1.30
1.00
35.50
39.50
6.00
5.00
22.70
18.46
2.99
2.74
Stem and leaf fresh weight
Root fresh weight
Stem and leaf dry weight
Root dry weight
Sturdiness quotient
Shoot/root ratio
0.23
0.04
0.03
0.01
4.53
0.31
2.76
1.47
0.76
0.57
18.10
6.00
1.26
0.57
0.34
0.15
7.72
2.56
Results & Discussion:
Correlation Analysis
Heavier seeds did tend to germinate
faster (P<0.01)
Earlier germination = head start = large
differences in seedling size and weight.
Results & Discussion:
Correlation Analysis
Morphological Trait
r value
Correlation Coefficient
Height
Main root length
Stem diameter
Number of leaves
0.85
0.36
0.77
0.65
Stem and leaf fresh weight
Root fresh weight
Stem and leaf dry weight
Root dry weight
Shoot/root ratio
0.90
0.83
0.88
0.71
0.18
Summary
This experiment found that fresh seed size
did effect emergence rate and the growth of
B. alicastrum seedlings.
Selection and planting of medium to
medium large seeds is recommended for
nursery production.